1/* $NetBSD: conf.c,v 1.14 2019/05/23 04:34:25 kre Exp $ */ 2 3/* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software donated to Berkeley by 8 * Jan-Simon Pendry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * from: Id: conf.c,v 1.2 1992/05/27 07:09:27 jsp Exp 35 * @(#)conf.c 8.2 (Berkeley) 3/27/94 36 */ 37 38#include <sys/cdefs.h> 39#ifndef lint 40__RCSID("$NetBSD: conf.c,v 1.14 2019/05/23 04:34:25 kre Exp $"); 41#endif /* not lint */ 42 43#include <sys/types.h> 44#include <sys/param.h> 45#include <sys/syslog.h> 46#include <stdio.h> 47#include <stdlib.h> 48#include <unistd.h> 49#include <string.h> 50#include <errno.h> 51#include <limits.h> 52#include <regex.h> 53 54#include "portald.h" 55 56#define ALLOC(ty) (xmalloc(sizeof(ty))) 57 58typedef struct path path; 59struct path { 60 qelem p_q; /* 2-way linked list */ 61 int p_lno; /* Line number of this record */ 62 char *p_args; /* copy of arg string (malloc) */ 63 char *p_key; /* Pathname to match (also p_argv[0]) */ 64 regex_t p_re; /* RE to match against pathname (malloc) */ 65 int p_use_re; /* true if entry is RE */ 66 int p_argc; /* number of elements in arg string */ 67 char **p_argv; /* argv[] pointers into arg string (malloc) */ 68}; 69 70static void ins_que(qelem *, qelem *); 71static path *palloc(char *, int, const char *); 72static void pfree(path *); 73static int pinsert(path *, qelem *); 74static void preplace(qelem *, qelem *); 75static void readfp(qelem *, FILE *, const char *); 76static void rem_que(qelem *); 77static void *xmalloc(size_t); 78 79/* 80 * Add an element to a 2-way list, 81 * just after (pred) 82 */ 83static void 84ins_que(qelem *elem, qelem *pred) 85{ 86 qelem *p = pred->q_forw; 87 elem->q_back = pred; 88 elem->q_forw = p; 89 pred->q_forw = elem; 90 p->q_back = elem; 91} 92 93/* 94 * Remove an element from a 2-way list 95 */ 96static void 97rem_que(qelem *elem) 98{ 99 qelem *p = elem->q_forw; 100 qelem *p2 = elem->q_back; 101 p2->q_forw = p; 102 p->q_back = p2; 103} 104 105/* 106 * Error checking malloc 107 */ 108static void * 109xmalloc(size_t siz) 110{ 111 void *p = malloc(siz); 112 113 if (p) 114 return p; 115 116 syslog(LOG_ERR, "malloc: failed to get %lu bytes", (u_long)siz); 117 exit(1); 118} 119 120/* 121 * Insert the path in the list. 122 * If there is already an element with the same key then 123 * the *second* one is ignored (return 0). If the key is 124 * not found then the path is added to the end of the list 125 * and 1 is returned. 126 */ 127static int 128pinsert(path *p0, qelem *q0) 129{ 130 qelem *q; 131 132 if (p0->p_argc == 0) 133 return 0; 134 135 for (q = q0->q_forw; q != q0; q = q->q_forw) { 136 path *p = (path *)q; 137 138 if (strcmp(p->p_key, p0->p_key) == 0) 139 return 0; 140 } 141 ins_que(&p0->p_q, q0->q_back); 142 return 1; 143 144} 145 146static path * 147palloc(char *cline, int lno, const char *conf_file) 148{ 149 int c, errcode; 150 char *s; 151 char *key; 152 path *p; 153 char **ap; 154 155 /* 156 * Do a pass through the string to count the number 157 * of arguments. Stop if we encounter a comment. 158 */ 159 c = 0; 160 key = strdup(cline); 161 for (s = key; s != NULL; ) { 162 char *val; 163 164 if (*s == '#') { /* '#" at beginning of word */ 165 cline[s-key] = '\0'; /* delete comment -> EOL */ 166 break; 167 } 168 169 while ((val = strsep(&s, " \t\n")) != NULL && *val == '\0') 170 ; 171 if (val) 172 c++; 173 } 174 c++; 175 free(key); 176 177 if (c <= 1) 178 return 0; 179 180 /* 181 * Now do another pass and generate a new path structure 182 */ 183 p = ALLOC(path); 184 p->p_argc = 0; 185 p->p_argv = xmalloc(c * sizeof(char *)); 186 p->p_args = strdup(cline); 187 ap = p->p_argv; 188 for (s = p->p_args; s != NULL; ) { 189 char *val; 190 191 while ((val = strsep(&s, " \t\n")) != NULL && *val == '\0') 192 ; 193 if (val) { 194 *ap++ = val; 195 p->p_argc++; 196 } 197 } 198 *ap = 0; 199 200#ifdef DEBUG 201 for (c = 0; c < p->p_argc; c++) 202 printf("%sv[%d] = %s\n", c?"\t":"", c, p->p_argv[c]); 203#endif 204 205 p->p_key = p->p_argv[0]; 206 p->p_use_re = 0; 207 if (strpbrk(p->p_key, RE_CHARS)) { 208 errcode = regcomp(&p->p_re, p->p_key, REG_EXTENDED|REG_NOSUB); 209 if (errcode == 0) 210 p->p_use_re = 1; 211 else { 212 char buf[200]; 213 regerror(errcode, &p->p_re, buf, sizeof(buf)); 214 215 syslog(LOG_WARNING, "%s, line %d: regcomp \"%s\": %s", 216 conf_file, p->p_lno, p->p_key, buf); 217 } 218 } 219 p->p_lno = lno; 220 221 return p; 222} 223 224/* 225 * Free a path structure 226 */ 227static void 228pfree(path *p) 229{ 230 free(p->p_args); 231 free((char *)p->p_argv); 232 if (p->p_use_re) 233 regfree(&p->p_re); 234 free((char *)p); 235} 236 237/* 238 * Discard all currently held path structures on q0. 239 * and add all the ones on xq. 240 */ 241static void 242preplace(qelem *q0, qelem *xq) 243{ 244 /* 245 * While the list is not empty, 246 * take the first element off the list 247 * and free it. 248 */ 249 while (q0->q_forw != q0) { 250 qelem *q = q0->q_forw; 251 rem_que(q); 252 pfree((path *)q); 253 } 254 while (xq->q_forw != xq) { 255 qelem *q = xq->q_forw; 256 rem_que(q); 257 ins_que(q, q0); 258 } 259} 260 261/* 262 * Read the lines from the configuration file and 263 * add them to the list of paths. 264 */ 265static void 266readfp(qelem *q0, FILE *fp, const char *conf_file) 267{ 268 char cline[LINE_MAX]; 269 int nread = 0; 270 qelem q; 271 272 /* 273 * Make a new empty list. 274 */ 275 q.q_forw = q.q_back = &q; 276 277 /* 278 * Read the lines from the configuration file. 279 */ 280 while (fgets(cline, sizeof(cline), fp)) { 281 path *p = palloc(cline, nread+1, conf_file); 282 283 if (p && !pinsert(p, &q)) 284 pfree(p); 285 nread++; 286 } 287 288 /* 289 * If some records were read, then throw 290 * away the old list and replace with the 291 * new one. 292 */ 293 if (nread) 294 preplace(q0, &q); 295} 296 297/* 298 * Read the configuration file (conf) and replace 299 * the existing path list with the new version. 300 * If the file is not readable, then no changes take place 301 */ 302int 303conf_read(qelem *q, const char *conf) 304{ 305 FILE *fp = fopen(conf, "r"); 306 307 if (fp) { 308 readfp(q, fp, conf); 309 (void)fclose(fp); 310 return 0; 311 } else { 312 int sverrno = errno; 313 314 syslog(LOG_WARNING, "open config file \"%s\": %m", conf); 315 errno = sverrno; 316 return -1; 317 } 318} 319 320 321char ** 322conf_match(qelem *q0, char *key) 323{ 324 qelem *q; 325 326 for (q = q0->q_forw; q != q0; q = q->q_forw) { 327 path *p = (path *)q; 328 329 if (p->p_use_re) { 330 if (regexec(&p->p_re, key, 0, NULL, 0) == 0) 331 return p->p_argv + 1; 332 } else { 333 if (strncmp(p->p_key, key, strlen(p->p_key)) == 0) 334 return p->p_argv + 1; 335 } 336 } 337 338 return 0; 339} 340